A polyamide resin has excellent mechanical properties and excellent heat resistance as well as excellent chemical resistance, and therefore has been developed as engineering plastics in a variety of applications and used by way of various molding methods. Especially, the use of the polyamide resin as a blow molded article produced by blow molding is expanding.
In connection with the above, a blow molding material comprising a polyamide resin composition which comprises two types of aliphatic polyamide resins, an aromatic polyamide resin, and an impact-resistant material has been proposed, and has been reported to have excellent blow moldability and impact resistance (see, for example, patent document 1). Further, a thermoplastic composition which is capable of being blow molded, and which comprises a thermoplastic resin, a viscosity modifier, a nitrogen-containing hindered phenolic antioxidant, a multifunctional ester group-containing hindered phenolic antioxidant, and a mixture of a copper salt and a potassium halide has been proposed, and has been reported to have excellent weldability (see, for example, patent document 2).